Wireless communication systems are widely known in which base stations (also known as eNodeBs (evolved Node Bs (eNBs))) communicate with mobile devices (also known as user equipments (UEs)) which are within range of the eNB. Each eNB divides its available bandwidth, i.e. frequency and time resources, into different resource allocations for the different UEs. There is a constant need to increase the capacity of such systems, and to improve the efficiency of resource utilisation, in order to accommodate more users (more UEs), more data-intensive services and/or higher data transmission rates.
Feedback about the status of a downlink channel between the eNB and the UE may be employed in order to optimise transmission of data over the downlink channel. In particular, the UE may determine downlink channel status information (CSI) from received pilot signals, and then communicate the CSI to the eNB. The eNodeB may use this data to determine a precoding for subsequent data transmissions to the UE.
A problem with MIMO systems of the prior art is that there performance is in certain circumstances.
There is therefore a need to improve MIMO precoding performance.
It will be clearly understood that, if a prior art publication is referred to herein, this reference does not constitute an admission that the publication forms part of the common general knowledge in the art in Australia or in any other country.